Chemical variation with altitude and longitude on exo-Neptunes: Predictions for Ariel phase-curve observations

Julianne I Moses (1) , Pascal Tremblin (2) , Olivia Venot (3) , Yamila Miguel (4)

1 SSI - Space Science Institute [Boulder]
2 MDLS - Maison de la Simulation
3 LISA (UMR_7583) - Laboratoire Interuniversitaire des Systèmes Atmosphériques
4 Leiden Observatory [Leiden]

Using two-dimensional (2D) thermal structure models and pseudo-2D chemical kinetics models, we explore how atmospheric temperatures and composition change as a function of altitude and longitude within the equatorial regions of closein transiting Neptune-class exoplanets at different distances from their host stars. Our models predict that the day-night stratospheric temperature contrasts increase with increasing planetary effective temperatures T eff and that the atmospheric composition changes significantly with T eff. We find that horizontal transport-induced This work was supported by the National Aeronautics and Space Administration under grant number NNX16AC64G issued through the Exoplanets Research Program.

Domaines: Planétologie et astrophysique de la terre [astro-ph.EP]

Julianne I Moses, Pascal Tremblin, Olivia Venot, Yamila Miguel. Chemical variation with altitude and longitude on exo-Neptunes: Predictions for Ariel phase-curve observations. Experimental Astronomy, 2021, ⟨10.1007/s10686-021-09749-1⟩. ⟨hal-03406736⟩